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At 1305 CDT, on 10-10-12 the Plant Shift S … At 1305 CDT, on 10-10-12 the Plant Shift Superintendent (PSS) was notified that during reviews of paperwork for a customer, it was discovered that four clean, empty cylinders used for transfer did not have a hydrocarbon test performed prior to filling, in violation of NCSA 360-005. NCSA 360-005 requires a test for never used non-USEC owned cylinders prior to filling to detect the presence of hydrocarbons. The presence of moderator in the cylinders could lead to either an 'explosion' that ruptures the cylinder and releases UF6 or criticality from moderation of greater than a safe mass of uranium. The controls ensure that double contingency exits to prevent filling a cylinder containing enough moderator to support criticality.</br>Cylinders affected are GE0195, GE0191, JM0226, and GE0407 and were filled on 9/16/12 and 9/22/12.</br>Since one leg of double contingency was lost, this is being reported to the NRC as a 24-hour Event Report in accordance with NRC BL 91-01 Supplement 1.</br>The NRC Resident Inspector has been notified of this event. PGDP Problem Report No. ATRC-12-2554; PGDP Event Report No. PAD-2012-06.</br>Responsible Division: Production Support & Product Scheduling</br>SAFETY SIGNIFICANCE OF EVENTS: A control relied upon for double contingency was violated. A cold pressure check and cylinder weight check performed prior to initial transfer of UF6 did not indicate the presence of moderator, and customer compliance with ANSI N14.1 also ensures that cylinders received at PGDP would not contain moderator. There was no indication of an adverse reaction noted during the filling of the cylinders. A cold pressure check performed after filling and cooldown did not indicate that an adverse reaction associated with UF6 and moderator had occurred. The introduction of UF6 eliminates the possibility of any residual moderator remaining in the cylinder; therefore, the cylinders are now in compliance with double contingency.</br>POTENTIAL CRITICALITY PATHWAYS INVOLVED: In order for criticality to be possible, sufficient undetected moderator would have to be present in the cylinder prior to the initial transfer of UF6. Although a control was violated, the cold pressure check ensured the moderation parameter was not exceeded.</br>CONTROLLED PARAMETERS: Double contingency for this scenario is provided by two controls on moderation.</br>ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL: 20,000 lbs. of UF6 at approximately 4.0% U235 enrichment. Plant limit is 5.5 wt.% U235 enrichment</br>NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES: The first leg of double contingency is based on cylinder compliance with ANSI N14.1 and the performance of a cold pressure check prior to initial transfer of UF6. ANSI N14.1 compliance ensures that the cylinders are clean and free of moderator. The cold pressure check provides a positive indication that no moderator is present inside the cylinder. The cold pressure check was adequately performed prior to initial UF6; therefore, this control was not violated.</br>The second leg of double contingency is based on performing a hydrocarbon test on the internal valve opening of the UF6 cylinder prior to initial transfer of UF6. The presence of hydrocarbon material in a UF6 cylinder could result in a cylinder rupture or criticality prior to initial transfer of UF6. The hydrocarbon test will give telltale signs that the inside of the cylinder may contain oil or other potential moderators. The hydrocarbon test was not performed; therefore, this control was violated. This leg of double contingency is considered to have been lost.</br>Since double contingency for this scenario is based on two controls on one parameter and a control was violated, double contingency was not maintained.</br>CORRECTIVE ACTIONS: None are needed.ntained.
CORRECTIVE ACTIONS: None are needed.
18:05:00, 10 October 2012 +
48,398 +
22:43:00, 10 October 2012 +
18:05:00, 10 October 2012 +
At 1305 CDT, on 10-10-12 the Plant Shift S … At 1305 CDT, on 10-10-12 the Plant Shift Superintendent (PSS) was notified that during reviews of paperwork for a customer, it was discovered that four clean, empty cylinders used for transfer did not have a hydrocarbon test performed prior to filling, in violation of NCSA 360-005. NCSA 360-005 requires a test for never used non-USEC owned cylinders prior to filling to detect the presence of hydrocarbons. The presence of moderator in the cylinders could lead to either an 'explosion' that ruptures the cylinder and releases UF6 or criticality from moderation of greater than a safe mass of uranium. The controls ensure that double contingency exits to prevent filling a cylinder containing enough moderator to support criticality.</br>Cylinders affected are GE0195, GE0191, JM0226, and GE0407 and were filled on 9/16/12 and 9/22/12.</br>Since one leg of double contingency was lost, this is being reported to the NRC as a 24-hour Event Report in accordance with NRC BL 91-01 Supplement 1.</br>The NRC Resident Inspector has been notified of this event. PGDP Problem Report No. ATRC-12-2554; PGDP Event Report No. PAD-2012-06.</br>Responsible Division: Production Support & Product Scheduling</br>SAFETY SIGNIFICANCE OF EVENTS: A control relied upon for double contingency was violated. A cold pressure check and cylinder weight check performed prior to initial transfer of UF6 did not indicate the presence of moderator, and customer compliance with ANSI N14.1 also ensures that cylinders received at PGDP would not contain moderator. There was no indication of an adverse reaction noted during the filling of the cylinders. A cold pressure check performed after filling and cooldown did not indicate that an adverse reaction associated with UF6 and moderator had occurred. The introduction of UF6 eliminates the possibility of any residual moderator remaining in the cylinder; therefore, the cylinders are now in compliance with double contingency.</br>POTENTIAL CRITICALITY PATHWAYS INVOLVED: In order for criticality to be possible, sufficient undetected moderator would have to be present in the cylinder prior to the initial transfer of UF6. Although a control was violated, the cold pressure check ensured the moderation parameter was not exceeded.</br>CONTROLLED PARAMETERS: Double contingency for this scenario is provided by two controls on moderation.</br>ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL: 20,000 lbs. of UF6 at approximately 4.0% U235 enrichment. Plant limit is 5.5 wt.% U235 enrichment</br>NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES: The first leg of double contingency is based on cylinder compliance with ANSI N14.1 and the performance of a cold pressure check prior to initial transfer of UF6. ANSI N14.1 compliance ensures that the cylinders are clean and free of moderator. The cold pressure check provides a positive indication that no moderator is present inside the cylinder. The cold pressure check was adequately performed prior to initial UF6; therefore, this control was not violated.</br>The second leg of double contingency is based on performing a hydrocarbon test on the internal valve opening of the UF6 cylinder prior to initial transfer of UF6. The presence of hydrocarbon material in a UF6 cylinder could result in a cylinder rupture or criticality prior to initial transfer of UF6. The hydrocarbon test will give telltale signs that the inside of the cylinder may contain oil or other potential moderators. The hydrocarbon test was not performed; therefore, this control was violated. This leg of double contingency is considered to have been lost.</br>Since double contingency for this scenario is based on two controls on one parameter and a control was violated, double contingency was not maintained.</br>CORRECTIVE ACTIONS: None are needed.ntained.
CORRECTIVE ACTIONS: None are needed.
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00:00:00, 10 October 2012 +
GDP-1 +
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23:15:01, 24 November 2018 +
22:43:00, 10 October 2012 +
0.193 d (4.63 hours, 0.0276 weeks, 0.00634 months) +
18:05:00, 10 October 2012 +
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